Electric battery rapid recharging system including a mobile charging station having a coolant supply line and an electrical supply line

ABSTRACT

A method for rapidly recharging a military or a non-military device having an electric battery is provided. The method includes recharging the military or non-military device and the recharging includes delivering coolant to the military or non-military device to cool the electric battery. A military device, a non-military non-vehicular device, a mobile charging station and a stationary charging station are also provided.

The present invention relates generally to electric battery rechargingand more specifically to an electric battery rapid recharging system andmethod for military and non-military applications.

BACKGROUND OF INVENTION

The military uses various devices in a number of different environmentsand for a number of different purposes. Military devices which includean electric battery are often used in an unpredictable and unforeseeablemanner and in locations where external electrical power is not readilyaccessible. Military devices which include an electric battery includearmed and unarmed transportation vehicles, artillery devices, and otherdevices carried in the field by military personnel. Extra batteries maybe carried in support of such military devices due to the limited energycontent of electric batteries and the length of time needed to rechargeelectric batteries. The weight and volume of the extra batteries mayimpair the mobility of military devices and personnel as well as addinghigher cost and disposal problems. While an increased battery energydensity would reduce the weight and volume of the extra batteries,unfortunately, the availability of batteries with increased energydensity is only slowly increasing. In non-military applications, extrabatteries may be purchased to avoid an inconveniently long time torecharge.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a method for rapidly recharging amilitary device having an electric battery. The method includes rapidlyrecharging the military device and the recharging includes deliveringcoolant to the military device to cool the electric battery.

A mobile rapid charging station is also provided. The mobile rapidcharging station includes a charging source providing an electricalcharge; a coolant source providing coolant; and a connector having bothan electrical supply section delivering the electrical charge and acoolant supply section delivering the coolant, and capable of connectingto a military device.

A military device is also provided. The military device includes anelectric battery powering the military device, a charging connectorreceptacle, a coolant conduit between the electric battery and thereceptacle, and an electrical power connection between the electricalbattery and the receptacle.

A non-military non-vehicular device is also provided. The non-militarynon-vehicular device includes an electric battery powering thenon-military non-vehicular device, a charging connector receptacle, acoolant conduit between the electric battery and the receptacle and anelectrical power connection between the electric battery and thereceptacle.

A method for rapidly recharging a device having an electric battery forpowering the military device is also provided. The method includesmoving a mobile charging station to the location of the device andrapidly recharging the electric battery using the mobile chargingstation. The recharging includes delivering coolant to the device tocool the electric battery during the recharging.

A method for rapidly recharging a device having an electric battery forpowering a device is also provided. The method includes moving a mobilecharging station to the location of the device and rapidly rechargingthe electric battery to at least a 50% capacity within ten minutes. Therecharging includes delivering coolant to the device to cool theelectric battery during the recharging.

A method for recharging a non-military non-vehicular device having anelectric battery is also provided. The method includes recharging thenon-military non-vehicular device. The recharging includes deliveringcoolant to the non-military non-vehicular device to cool the electricbattery.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is described below by reference to the followingdrawings, in which:

FIG. 1a schematically shows a rapid battery charging station forcharging military devices powered by electric batteries according to anembodiment of the present invention;

FIG. 1b schematically shows a mobile rapid battery charging station forcharging military devices powered by electric batteries according toanother embodiment of the present invention;

FIG. 2 schematically shows an electric battery for charging according toan embodiment of the present invention;

FIG. 3 shows a graph plotting battery temperature versus time for athree-cell battery rapidly charged at a 20 minute rate;

FIG. 4 schematically shows coolant flowing through interconnectors ofthe electric battery shown in FIG. 2;

FIG. 5 schematically shows an electric battery of a tank being chargedby a rapid battery charging station;

FIG. 6 schematically shows an electric battery of a rail gun beingcharged by a rapid battery charging station;

FIG. 7 schematically shows an aircraft as a mobile rapid batterycharging station; and

FIG. 8 schematically shows a marine vehicle as a mobile rapid batterycharging station.

DETAILED DESCRIPTION

Because of the unpredictable and unforeseeable manner and the remotelocations in which military devices are used, it may be advantageous topower the military devices using electric batteries that are quicklyrecharged using rapid recharging stations that are mobile or are locatedat military bases. Combining the availability of rapid charging withovernight charging, may further increase the convenience and appeal ofpowering military devices with electric batteries. Increased productionof rapidly-rechargeable electric batteries and rapid recharging stationsfor military purposes may also achieve economies of scale that mayincrease the use of rapidly-rechargeable electric batteries and rapidrecharging stations in non-military vehicles and non-militarynon-vehicular applications.

Embodiments of the present invention provide high power DC electricsupply charging stations capable of delivering up to 300 kW per electricbattery (e.g., for 6 minutes charging of a 30 kWh electric battery) ormore together with a coolant for cooling the electric battery duringcharging so that the battery does not overheat (up to ˜50 kW of heat forexample may be expected to be generated during 6 minutes of chargetime). Conventional cooling techniques, such as cooling the surface orexterior of high voltage electric batteries, may not efficiently coolthe heat generated by rapid charging stations delivering up to 300 kW ormore per electric battery. Because heat generated by charging isprimarily generated internally within the electric battery, cooling theexternal surface of the electric battery is inefficient and hightemperature gradients within the battery stack itself may lead tobattery damage and early failure due to an undesirable rise intemperature, increasing costs and the likelihood of dangerous thermalrunaway of the battery.

Further, embodiments of the present invention may allow for an efficientand safe method of internal battery stack cooling during high ratecharging and may provide a unique and highly effective universal thermalmanagement system. Additionally, the embodiments only add minimalonboard volume and weight to military devices powered by electricbatteries because the coolant and an optional heat exchanger areexternal to the military devices and are applied only during charging.

FIGS. 1a and 1b schematically show rapid charging stations 10 a, 10 brespectively for charging military devices 20 or non-military devicespowered by electric batteries 30 according to embodiments of the presentinvention. In some preferred embodiments, military devices 20 includeland combat and transportation vehicles, such as armored personnelcarriers, light armored vehicles, mine protected vehicles,self-propelled howitzers, 4×4 utility vehicles, command and forwardobservation vehicles, self-propelled mortars, self-propelled guns, tanks110 (as schematically shown in FIG. 5), artillery trucks, air defensecommand vehicles, C4i equipment, unmanned combat vehicles (i.e.,drones), robots and infantry fighting vehicles. In other preferredembodiments, military devices 20 include stationary applicationsincluding battery powered back-up systems and UPS for command andcontrol systems such as C4i and for hospitals as well as primary energysources for artillery devices such as rail guns 120, as schematicallyshown in FIG. 6. In additional preferred embodiments, military devices20 include devices carried by military personnel, such as power packs,radios, handheld computers, Global Positioning Systems and encryptiondevices. In even further preferred embodiments, military devices 20include components of command stations, such as telemetry systems. Inmore preferred embodiments, military devices 20 include aircraft andmarine vehicles.

In other embodiments, rapid charging stations 10 a, 10 b may be used forcharging non-military devices that are powered by electric batteries. Inpreferred embodiments, non-military devices may include non-vehicularapplications powered by batteries and examples of such non-militarydevices benefiting from rapid recharging include power tools, portableelectronics, video cameras, UPS back-up systems, emergency lighting,computers, servers, back-up generators, telemetry systems, medicalequipment and other devices powered by electric batteries may be chargedby rapid charging stations 10 a, 10 b. In additional preferredembodiments, non-military devices may include electric vehiclesincluding cars, trucks, electric boats, ships and aircraft.

FIG. 2 shows one exemplary embodiment of electric battery 30 in moredetail. Electric battery 30 may be a modular battery including aplurality of battery cells 32 separated by a plurality of internalchannels 34 in battery 30 in between cells 32. Channels 34 arepreferably at least partially filled with porous compressibleinterconnectors 36, which act to provide an electrically-conductinginterconnection between adjacent cells 32 while also allowing coolant tobe passed through internal channels 34 between cells 32 to cool cells 32during charging. FIG. 4 schematically shows coolant 100 flowing throughchannels 34 and through interconnectors 36 of the electric battery 30.In preferred embodiments, battery 30 is the battery disclosed in U.S.Pub. No. 2009/0239130, which is hereby incorporated by reference herein,with interconnectors 36 and cells 32 being formed in the same manner asthe interconnectors and the planar cell modules, respectively, disclosedin U.S. Pub. No. 2009/0239130. Cells 32 each include a positive and anegative electrode, with the positive electrodes connecting to apositive terminal 39 and the negative electrodes connecting to anegative terminal 40.

Compressible interconnectors 36 can be made any material that hassufficient properties such as, for example a wire mesh, metal or carbonfibers retained in a compressible elastomeric matrix, or an interwovenconducting mat, consistent with the requirement for a compressibleflexible electrically-conducting interconnection between adjacent cellplate module surfaces while maintaining sufficient spacing for coolantto be passed through internal channels 34 to cool cells 32 duringcharging. In the illustrative example in FIG. 2, six cells 32 arecontained in a stacked array within an enclosure 25 which, in thisembodiment, is of rectangular cross section. Although only six cells 32are shown, battery 30 may include tens to hundreds of cellsinterconnected to make a very high-voltage battery stack. Enclosure 25includes inputs and outputs, which may be automatically opened orclosed, allowing coolant to be passed through channels 34.

In alternative preferred embodiments, interconnectors 36 may not beelectrically and/or thermally conductive, but may simply be providedbetween cells 32 to space cells 32 apart from each other to formchannels 34 between cells. In these embodiments, cells 32 may be formedas insulating pouches with conductive tabs at the ends thereof whichallow coolant passing through channels 34 formed by interconnectors 36to cool cells 32.

The power terminals 39, 40 connect internally to the ends of the cellmodule battery stack through an internal power bus 28 for the positiveterminal 39 and electrically conductive enclosure 25 may serve as anegative bus 29 to negative terminal 40 or a negative bus mayadditionally be provided for negative terminal 40. Enclosure 25 mayprovided with external multipin connectors 37, 38, which may beelectrically connected by sense lines to electrical feed throughs 35,for monitoring cell voltage and cell temperature, respectively. One setof multipin connectors 37, 38 may be provided for each cell 30. In orderto provide cell voltage and cell temperature information for controllingthe charging of battery 30, multipin connectors 37, 38 may transmitvoltage and cell temperature measurements to controller 28 (FIG. 1).

Referring back to FIGS. 1a, 1b , electric batteries 30 may be eachcoupled to controller 28 in military device 20, which may determine thestate of battery 30 and regulate the operation and charging of batteries30 accordingly.

In FIG. 1a , charging station 10 a is located on a military base 100 ora supermarket or other convenient place and is stationary or non-mobileand may be used for charging handheld military or non-military devices,which may be for example handheld computers 20 a. Charging station 10 amay include a high power charging source 12 for rapidly charging battery30 and a coolant source 14 for supplying coolant internally to battery30 via channels 34 (FIG. 2) as battery 30 is rapidly charged by highpower charging source 12, which in a preferred embodiment is a highpowered DC power source such as an AC/DC power supply connected to astandard AC electrical supply or a diesel-generator, or alternatively abattery, a bank of batteries or super capacitor capable of dischargingat high rates and being recharged with off-peak electricity, which ischeaper and less likely to cause power grid disruptions. When chargingsource 12 includes a battery, a bank of batteries or super capacitorsupplying power to battery 30, charging source 12 includes a gas orliquid cooling system as described herein for battery 30 to reduce anundesirable rise in temperature of the battery, bank of batteries orsuper capacitor of charging source 12. The amount of cooling required bythe charging source battery 12 will depend upon the relative size of thebattery, bank of batteries or super capacitor of charging source 12compared to the battery 30 being charged. If the battery, bank ofbatteries or super capacitor of charging source 12 is ten times largerin battery capacity than the capacity of the battery 30 being chargedthen no active cooling of the battery, bank of batteries or supercapacitor of charging source 12 may be required. A person may bringhandheld computer 20 a to charging station 10 a, which in thisembodiment is stationary, but in other embodiments may be mobile, andplug a connector 18 c of a supply line 18 of charging station 10 a intoa receptacle 27 in handheld computer 20 a. In the embodiment shown inFIG. 1a , supply line 18 extends outside of a base portion 22 of rapidcharging station 10 a and includes an electrical supply line 18 acoupled to high power charging source 12 and a coolant supply line 18 bcoupled to coolant source 14. Connector 18 c may be inserted intoreceptacle 27 of handheld device 20 such that connector 18 c istemporarily locked into place in receptacle 27. After charging station10 a begins charging, rapid charging station 10 a provides current fromhigh power charging source 12 and coolant from coolant source 14 tobattery 30 until battery 30 is sufficiently charged. In one preferredembodiment of the present invention, rapid charging station 10 a maycharge battery in less than 15 minutes. During charging, sufficientcoolant may be pumped from coolant source 14 through supply line 18 andcoolant conduit 26 into battery 30 as current is supplied from highpower charging source 12 through supply line 18 and electrical conduit24 to absorb a portion of the heat generated within battery 30 andprevent battery 30 from being damaged or destroyed during the chargingdue to an undesirable rise in temperature.

For non-military devices rapid charging station 10 a could be locatednear or within a supermarket or other convenient public location forrapid charging of devices including for example electric scooters, golfcarts, bicycles, laptop computers and phones. Stationary or non-mobilecharging station 10 a may be sufficiently powerful to rapidly charge amuch larger battery such as an electric vehicle battery, for example a30 kWh electric vehicle, and may be used to rapidly recharge anoff-board or on-board electric vehicle battery. Rapid recharging of anelectric vehicle battery removed from the electric vehicle (off-board)using rapid charging station 10 a may avoid the need to replace theremoved electric vehicle battery with another that is prior fullycharged at a slower recharge rate thereby reducing the requirement for alarge fully-charged replacement battery standing by or in inventory.These examples illustrate the benefits of embodiments the presentinvention for reducing the number of replacement batteries needed for avariety of battery powered military and non-military applications. Theavailability and convenience of rapid recharging stations diminishes theneed for purchasing extra batteries and the longevity provided by themultiple rechargeability of batteries utilizing embodiments of thepresent invention may provide environmental and strategic benefits forthe United States by reducing battery raw materials importation andprocessing thereof. For military applications the present invention mayhelp reduce battery stockpiles and logistical battery inventories.

In FIG. 1b , charging station 10 b is a mobile charging station, a socalled mule, which may be strategically moved to locations whereelectric batteries 30 of military devices 20 need to be rapidly chargedin order to allow electric batteries 30 of military devices 20 to berapidly charged between overnight or standard charges (i.e., charges inwhich batteries 30 are charged slowly by stationary charging stationsfor multiple hours). For example, mobile charging stations 10 b may beground vehicles, aircraft 130, as schematically shown in FIG. 7, ormarine vehicles 140, as schematically shown in FIG. 8, or may beincluded on or in (either integrally or removably) ground vehicles,aircraft or marine vehicles. In this embodiment, military device 20 is acommand station 20 a.

In a further embodiment, mobile rapid recharging station 10 b isincluded with an Integrated Generator-Environmental Control Unit(ECU)-Trailer (ITEG or GET) for military life-support, command andcontrol systems in forward operations centers. The cool air generated bythe ECU of the ITEG or GET Trailer is passed through the channels 34 ofbattery 30 to cool the battery without the need for battery coolantsource 14. With reference to FIG. 1b , high power charging source 12 maybe the Integrated Generator of the ITEG or GET Trailer and coolantsource 14 may be replaced by the ECU, allowing battery 30 to be rapidlyrecharged for use as a mobile rapid recharging station. Mobile chargingstations of the present invention can be used to recharge batteries innon-mobile or other mobile devices including vehicles, boats, ships andaircraft. For non-military devices a mobile rapid charging station couldbe deployed in emergencies to distant devices with depleted batteryenergy such as stranded electric vehicles and remote UPS back-upfacilities.

Mobile charging stations 10 b may include high power charging source 12for rapidly charging battery 30 and coolant source 14 for supplyingcoolant internally to battery 30 via channels 34 (FIG. 2) as battery 30is rapidly charged by high power charging source 12. Mobile chargingstation 10 b may be moved to the location of one or more of militarydevices 20 and connector 18 c on the end of a supply line 18 of mobilecharging station 10 b may be inserted either manually or automaticallyor robotically into a corresponding receptacle 27 of military device 20.In the embodiment shown in FIG. 1b , supply line 18 extends outside of abase portion 22 of mobile charging station 10 b and includes anelectrical supply line 18 a coupled to high power charging source 12 anda coolant supply line 18 b coupled to coolant source 14. Connector 18 cmay be inserted into receptacle 27 of command station 20 b such thatconnector 18 c is temporarily locked into place in receptacle 27. Aftermobile charging station 10 b begins charging, rapid charging station 10b provides current from high power charging source 12 and coolant fromcoolant source 14 to battery 30 until battery 30 is sufficientlycharged. In one preferred embodiment of the present invention, mobilecharging station 10 b delivers up to 300 kW to command center 20 b andmay accordingly charge a 600 Volt, 30 kWh embodiment of battery 30, inapproximately 6 minutes. During the approximately 6 minutes of rapidcharging of the 30 kWh embodiment of battery 30, approximately 50 kW ofheat may be generated by cells 32 of the 30 kWh embodiment of battery30. Without coolant being provided preferably internally to the 30 kWhembodiment of battery 30 during such rapid charging, battery 30 maybecome permanently damaged or destroyed due to an undesirable rise intemperature. Accordingly, sufficient coolant may be pumped from coolantsource 14 through supply line 18 and coolant conduit 26 into battery 30as current is supplied from high power charging source 12 through supplyline 18 and electrical conduit 24 to absorb a portion of the heatgenerated within battery 30 and prevent battery 30 from being damaged ordestroyed during the charging due to an undesirable rise in temperature.

Accordingly, a method for recharging military devices 20 each having anelectric battery 30 may include moving the mobile charging station 20 b,via a ground vehicle, an aircraft or a marine vehicle, to a location ofa first military device, then connecting the connector 18 c toreceptacle 27 of the first military device. The first military devicemay be one of a land combat or transportation vehicle, a stationaryartillery device, a device carried by military personnel or a componentof a command station. The method may then include recharging electricbattery 30 of the first military device via the mobile charging station20 b by supplying electricity from the charging source 12. The electricbattery 30 of the first military device including a plurality of cells32 stacked inside of an enclosure 25, as shown in FIG. 2. The rechargingmay include delivering coolant from the coolant source 14 through theconnector 18 c to the first military device to cool the electric battery30 so that coolant flows through the enclosure 25. The method may theninclude moving the mobile charging station 20 b, via the ground vehicle,the aircraft or the marine vehicle, to a location of a second militarydevice for recharging an electric battery 30 of the second militarydevice.

In an alternative embodiment, in particular for use when the coolantprovided by coolant source 14 is oil or another liquid, but alsopossibly when the coolant provided is air or another gas, a coolantreturn conduit may be provided in each of military devices 20 at theoutput ends of channels 34 to cycle the coolant that has been passedthrough battery 30 back through supply line 18 into coolant source 14.In this alternative embodiment, an additional coolant return line,either integral with supply line 18 or independent of supply line 18,may also be provided between military device 20 and rapid chargingstation 10 a, 10 b to recycle the coolant back into coolant source 14.Rapid charging stations 10 a, 10 b may then be provided with a heatexchanger for removing the heat generated within battery 30 from therecycled coolant.

In another alternative embodiment, instead of rapid charging stations 10a, 10 b including single supply line 18, current from high powercharging source 12 and coolant from coolant source 14 may be provided tomilitary devices 20 separately, such that two independent supply linesare provided between rapid charging station 10 a, 10 b and militarydevices 20. For example, the two independent supply lines may be a cablecoupled to high power charging source 12 having a connecting plug forremovable attachment to an electrical receptacle coupled to electricalconduit 24 and a hose coupled to coolant source 14 having a connectingnozzle for removable attachment to a separate coolant receptacle coupledto coolant conduit 26. In further embodiments of the present invention asupply line may only be used for coolant source 14 and high powercharging source 12 may wirelessly charge battery 30 through inductivecharging or magnetic resonance charging. In another alternativeembodiment, a separate coolant return may be provided and connected to aheat exchanger in rapid charging stations 10 a, 10 b.

Rapid charging stations 10 a, 10 b may each include a controller 70 forcontrolling the amount of charge supplied to battery 30 from high powercharging source 12 and to control the amount of coolant supplied tobattery 30 from coolant source 14 (and back into coolant source 14 inembodiments where the coolant is recycled). As military devices 20 areconnected to mobile charging stations 10 a, 10 b for charging battery30, controller 70 may be brought into communication with controller 28of battery 30 such that controller 70 can regulate the supply of chargefrom high power charging source 12 and the supply of coolant fromcoolant source 14 according to the present state of battery 30. Forexample, if due to the weather conditions or the manner in whichmilitary device 20 has been driven, battery 30 is warmer or cooler thanusual (for example as measured by connectors 37, 38 shown in FIG. 2),the supply rate and/or temperature of coolant from coolant source 14 maybe increased or decreased accordingly. Also, if battery 30 is partiallycharged and only needs to be charged a small amount, controller 70 canlimit the supply of charge from high power charging source 12 to belowthe maximum charging rate and adjust the flow rate and/or temperature ofcoolant from coolant source 14 to a corresponding value. Controller 70may include a memory that correlates the amount of coolant to besupplied to the charge supplied and also optionally to the temperatureof battery 30. Controller 28 may also provide controller 70 withinformation regarding the present chemistry and history of battery 30,as sensed at battery 30, and controller 70 may control the charging andcooling of battery 30 based on the chemistry and history of battery 30to allow for the safest protocols for recharging battery 30. Forexample, an older battery 30 may not take the fastest recharging ratesor may have a slightly different chemistry and may be charged by mobilecharging station 10 a, 10 b according to preset charging and coolingrates stored in controller 70.

In one example, battery 30 is a 300 Volt electric battery weighing 100kg and after a full charge may supply 30 kWh to military device 20. Inthis example, high power charging source 12 fully charges battery 30 inten minutes, at 180 kW and battery 30 includes one hundred 3V cells 32each having a resistance of 1 milliohm. The charging generatesapproximately 36 kW of heat for 10 minutes (˜6 kWh). In order tosufficiently cool battery 30 during such charging to maintain anacceptable temperature of approximately 45 degrees Celsius, coolantsource 14 may provide oil (supplied at 20 degrees Celsius) at a rate ofat least 0.73 liters per second (44 liters per minute) or may provideair (supplied at 0 degrees Celsius) at a rate of at least 1800 cubicfeet per minute. Across the industry, electric battery charge anddischarge rates are referred to using a normalization called a C-rate(C=capacity of the battery). Regardless of the size of an electricbattery, a 1 C rate on charge or discharge means the battery is fullycharged or discharged or discharged in 1 hour. For example a C/8 ratewould indicate an eight hour charge or discharge and 2 C rate wouldindicate a half hour charge or discharge. Accordingly, for the aboveexample of charging in ten minutes, battery 30 would have a C-rate of 6C.

In another example, to charge a 600 Volt, 24 kWh embodiment of battery30 in six minutes, high power charging source 62 may be a 240 kWcharger, delivering 400 Amps at 600 Volts (DC) for six minutes. Due tosubstantial heat losses, the power delivered may have to be much higherthan if the charging was completely efficient. For example, if therewere two hundred cells of 3 Volts each, with a resistance each of onemilliohm, there may be 32 kW of heat generated, and an additional minuteof charging (approximately seven minutes total) may be necessary.

In one embodiment, instead of fully charging battery 30 to 100% of itscharge capacity using high power charging source 12, battery 30 may becharged by high power charging source 12 to 80% of its charge capacityin approximately five minutes. This approach of 80% charging may preventovervoltages in some cells of battery 30. Charging over 80% of thecharge capacity of battery 30 may then be accomplished if desirable bytapering down the current supplied by charging source 12 after battery30 is charged to 80% of its charge capacity. In order to charge the 600Volt, 24 kWh embodiment of battery 30, after being fully discharged,having two hundred cells of 3 Volts each, with a resistance each of onemilliohm, to 80% capacity (19.2 kWh) in five minutes, 2.7 kWh of heat(32 kW over five minutes ˜10⁷ Joules) would be generated in battery 30.In order to sufficiently remove 2.7 kWh of heat in five minutes, oil maybe passed internally through channels 34 of battery 30 at a minimum of40 liters/min or air may be passed internally through channels 34 ofbattery 30 at a minimum of 1600 cubic ft/min. In order to compensate forthe inherent delay in heat transfer to the coolant, in preferredembodiments of the present invention, oil or air is passed through athigher rates than the minimum. In these embodiments, for the abovementioned 600 Volt battery, oil may be passed internally throughchannels 34 of battery 30 at approximately 50 to 200 liters/min or airmay be passed internally through channels 34 of battery 30 atapproximately 2000 to 8000 cubic ft/min. The cooling rates for larger orsmaller batteries may be proportionately higher or lower, respectively.

A refrigeration unit 16 may be included in rapid charging stations 10 a,10 b for further cooling the air or oil used to cool battery 30. Inparticular, refrigeration unit 16 may be particularly advantageous forcooling air and may allow air to be passed internally through channels34 of battery 30 at rates lower than approximately 2000 to 8000 cubicft/min.

In some embodiments, after battery 30 is rapidly charged by rapidcharging station 10 a or 10 b, battery 30 may be internally air-cooledor heated by passing air through interconnectors 36. The air may besupplied using blown air from an existing on-board air conditioning orair-heating system (HVAC) present on certain embodiments of militarydevice 20 (e.g., at least some of the transportation and combatvehicles). For instance, air-blown heating may be used during thecoldest days of winter months for efficient and rapid battery warm up,which is advantageous because batteries loose considerable capacity atlow temperatures. Then, as the battery heats up to the normal operatingtemperature, any waste heat generated thereafter may be used for spaceheating or cooling (e.g., via a small heat pump), thereby utilizingotherwise wasted energy and controlling the rising of the temperature ofbattery 30 during accelerating and braking transients. In an alternativeembodiment, after battery 30 is charged by rapid charging stations 10 a,10 b, battery 30 may be internally liquid-cooled or liquid-heated bypassing liquid through interconnectors 36 from an on-board liquidheat-exchanger cooled or heated respectively by an on-boardrefrigeration or heating system.

In one embodiment of the present invention, coolant conduit 26 and thecoolant return conduit, if provided, may be incorporated into the HVACsystem present on certain embodiments of military device 20 (e.g., atleast some of the transportation and combat vehicles). Accordingly,coolant conduit 26 and the coolant return conduit may be used forthermal management of battery 20 to pass coolant through channels 34(FIG. 2) during the operation of military device 20 and then for coolingof battery 30 with coolant supplied by rapid charging stations 10 a, 10b and passed through channels 34 during rapid recharging. Switchingvalves could be provided to alternately couple the coolant conduit 26and the coolant return conduit to the HVAC system during operation ofmilitary device 20 and to supply line 18 during charging.

Additionally, for example, the thermal energy removed from battery 30 bythe coolant passing through battery 30 may be converted into electricityin either military device 20 or rapid charging stations 10 a, 10 b. Forexample, turbine or thermoelectric devices of military device 20 orturbine or thermoelectric devices in rapid charging stations 10 a, 10 bmay be coupled to outlets of channels 34 to recapture energy in thecoolant downstream of battery 30.

In preferred embodiments, battery 30 contains nanoscale particles whichfundamentally allow for high charging rates. The nanoscale particles maybe coated with a thin layer of carbon. For example, anodes of cells 32may be formed of lithium titanium oxide (LTO) nanoparticles and cathodesof cells 32 may be formed of lithium iron phosphate (LFP) nanoparticles,such that battery 30 may be rapidly recharged at up to the 3 minute rate(i.e., 20 C-rate) and may also cycle for many thousands of times suchthat no battery replacement may be required during the life of militarydevice 20. For example, the use of such nanoparticles in battery 30 whencombined with the present invention which limits the temperature rise inbattery 30 may allow battery 30 to be rapidly charged more than 10,000times. Such battery longevity would yield a high salvage value forbattery 30. Such battery longevity would also provide environmental andstrategic benefits for the United States by reducing battery rawmaterials importation and processing thereof and by reducing batterystockpiles and logistical battery inventories.

Coolants other than air or oil may also be supplied by coolant source14. For example, flowable liquid or gaseous materials having optimalheat capacity may used. The coolant may be supplied with additives toincrease heat exchange capabilities. In one preferred embodiment, thecoolant is electrically insulating.

In further embodiments of the present invention, stationary rapidcharging stations may be used and the military devices 20 may betransported, possibly via an additional vehicle, to the stationary rapidcharging stations. Also, in further embodiments, battery 30 may beremoved from the military device 20 and replaced with a backup batterywhile battery 30 is charged by mobile charging station 10 b or taken toa stationary charging station for charging. In even further embodiments,military device 20 may include two or more batteries 30 and one of thebatteries may power military device 20 while the other battery 30 ischarged.

FIG. 3 shows a graph plotting battery core temperature versus time for athree cell battery rapidly charged at a 20 minute rate (i.e., 3 C-rate).The three cell battery includes electrically conductive interconnectors36 (FIG. 2) between the cells. A line 200 plots the temperature of thethree cell battery versus time without any coolant flowing throughinterconnectors 36 and a line 202 plots the temperature of the threecell battery versus time with coolant being pumped into the battery,through interconnectors 36, at a rate of one liter per minute. In thisexperiment, the coolant used was a commercial heat-transfer fluid,Paratherm LR, a paraffinic hydrocarbon with a broad operating range(i.e., between −50 and 230 degrees Celsius). Paratherm LR has a specificresistance of around 10E14 ohm cm, and the dielectric breakdown voltage(per ASTM D1816-04, 0.1 inch gap) is over 22 kV, which was sufficient toprevent damage to the electrical components of the battery for exampleby electrical shorting which would also cause inefficient charging. Thegraph illustrates that pumping coolant into a battery limits thetemperature of the battery. As shown in FIG. 3, without cooling, thebattery is heated from 22 degrees Celsius to 30 degrees Celsius inapproximately 4 minutes and is heated to approximately 39 degreesCelsius in approximately 11 minutes. In contrast, with coolant beingpumped through the battery, the battery does not reach 30 degreesCelsius until the battery has been heated for 11 minutes. Accordingly,the temperature increase in the cooled battery is less than half of thetemperature increase of the uncooled battery (8 degrees Celsius vs. 17degrees Celsius). Further properties of Paratherm LR are shown in thebelow chart.

Chemical name Paraffinic hydrocarbon Maximum Recommended Film 500°F./260° C. Temperature Maximum Recommended Operating 450° F./232° C.Temperature Minimum Operating Temperature 20 cPs −58° F./−50° C. (20mPa-s) Minimum Start-up Temperature 300 cPs −112° F./−80° C.  (300mPa-s) Viscosity at 60° F. cSt (mm²/sec) 2.4  Density at 60° F./15.5° C.lb/gal (kg/m³) 6.4 (766) Flash Paint Closed Cup (D56) >130° F./54° C. Autoignition Temperature (maximum 10 >500° F./260° C.  sec ignitiondelay) Boiling Point (14.7 psia/101 kPa) 397° F./202° C. Vapor Pressure@ maximum operating 21 (145) temperature psia (kPa) % Volume expansionover recommended 6.8 (12.2) operating temperature per 100° F. (° C.)Average Molecular Weight 160    Dielectric Breakdown voltage D1816-0422.15  (kV, 0.1″ gap) Dielectric Constant (1 KHz) D924-04 2.03Dissipation Factor (1 KHz) D924-04   0.00001 Volume Resistivity at 100 V(Ω-cm) D257- 1.84 × 10¹⁴ 07 Heat of combustion (approximate) BTU/lb20,000 (46,300) (kJ/kg) Heat of vaporization (approximate) Btu/lb 113(262) (kJ/kg)

In the preceding specification, the invention has been described withreference to specific exemplary embodiments and examples thereof. Itwill, however, be evident that various modifications and changes may bemade thereto without departing from the broader spirit and scope ofinvention as set forth in the claims that follow. The specification anddrawings are accordingly to be regarded in an illustrative manner ratherthan a restrictive sense.

What is claimed is:
 1. A mobile charging station comprising: a baseportion comprising: a charging source providing an electrical charge; acoolant source providing coolant; a supply line connected to thecharging source and the coolant source and extendible outside of thebase portion; and a connector fixed to an end of the supply line, theconnector being configured for insertion into a receptacle of a militarydevice, the supply line including a coolant supply line configured fordelivering coolant from the coolant source to the connector, the supplyline including an electrical supply line configured for deliveringelectrical charge from the charging source to the connector, theconnector having both an electrical supply section connected to theelectrical supply line for delivering the electrical charge and acoolant supply section connected to the coolant supply line fordelivering the coolant, and the connector being configured forconnecting to the military device, the mobile charging station being orincluded on or in a ground vehicle, an aircraft or a marine vehicle. 2.The mobile charging station as recited in claim 1 further comprising acontroller configured for regulating the supply of charge from thecharging source high power charging source and the supply of coolantfrom the coolant source according to a present state of a battery of themilitary device during charging.
 3. The mobile charging station asrecited in claim 1 wherein charging source is configured for deliveringup to 300 kW per electric battery.
 4. The mobile charging station asrecited in claim 1 wherein charging source is at least one battery or asuper capacitor.
 5. The mobile charging station as recited in claim 1wherein coolant source includes an electrically insulating oil.
 6. Amethod for recharging military devices each having an electric battery,the method comprising: moving the mobile charging station, via a groundvehicle, an aircraft or a marine vehicle, to a location of a firstmilitary device, the mobile charging station including a coolant source,a charging source, a supply line connected to the charging source andthe coolant source, and a connector connected to an end of the supplyline; connecting the connector to a receptacle of the first militarydevice, the first military device being one of a land combat ortransportation vehicle, a stationary artillery device, a device carriedby military personnel or a component of a command station; recharging anelectric battery of the first military device via the mobile chargingstation by supplying electricity from the charging source, the electricbattery of the first military device including a plurality of cellsstacked inside of an enclosure, the recharging including deliveringcoolant from the coolant source through the connector to the firstmilitary device to cool the electric battery so that coolant flowsthrough the enclosure; and moving the mobile charging station, via theground vehicle, the aircraft or the marine vehicle, to a location of asecond military device for recharging an electric battery of the secondmilitary device.
 7. The method as recited in claim 6 wherein the batteryincludes interconnectors spacing the cells apart, the delivering coolantto the military device to cool the electric battery including deliveringcoolant through the interconnectors.
 8. The method as recited in claim 6wherein the first military device is a land combat or transportationvehicle.
 9. The method as recited in claim 6 wherein the first militarydevice is a stationary artillery device.
 10. The method as recited inclaim 6 wherein the first military device is a device carried bymilitary personnel.
 11. The method as recited in claim 6 wherein thefirst military device is a component of a command station.
 12. Themethod as recited in claim 6 wherein the recharging uses an electricalpower that is more than 100 Watts.
 13. The method as recited in claim 6wherein the recharging takes less than an hour.
 14. The method asrecited in claim 6 wherein the electric battery of the first militarydevice and the electric battery of the second military device are eachrecharged to at least 50% capacity.
 15. The method as recited in claim 6wherein the coolant is gas supplied at 0.1 cubic ft/min or greater. 16.The method as recited in claim 6 wherein the coolant is liquid suppliedat 0.01 liters/min or greater.
 17. The method as recited in claim 6wherein the cells are spaced apart from each other by channels, therecharging including delivering coolant to the military device to coolthe electric battery so that coolant flows through the channels andcools the cells.